This application claims priority from Japanese Patent Application No. 2001-401669 filed Dec. 28, 2001, which is incorporated hereinto by reference.
1. Field of the Invention
The present invention relates to a method of manufacturing a structural body, a liquid tank and an ink jet printing apparatus and to an ink jet printing apparatus. More specifically the present invention relates to a method of manufacturing a structural body, a liquid tank and an ink jet printing apparatus, all having a porous film (hereinafter referred to as a xe2x80x9cgas-liquid separation membersxe2x80x9d) attached to a gas-liquid separation portion, and to an ink jet printing apparatus.
Further, the present invention relates to a method of manufacturing a structural body, such as a liquid tank, that has a communication portion for communicating an interior of the tank, into which a liquid is introduced, to an exterior thereof through an gas-liquid separation member permeable only to gases. The invention also relates to a liquid tank and a head cartridge manufactured by the manufacturing method and an ink jet printing apparatus that uses the liquid tank and the head cartridge.
2. Description of the Related Art
Ink jet printing apparatus have come into rapidly expanding use in recent years thanks to their advantages of being able to perform color printing and reduce the size of apparatus relatively easily. Particularly a serial type ink jet printing apparatus, which can easily be reduced in size, is in widespread use. In the serial type, however, since the printing is done by scanning a carriage that mounts a print head, there is a limit to the weight that can be carried by the carriage in order to ensure its normal operation. Hence, an ink tank integrally formed with the print head (hereinafter referred to as a xe2x80x9csubtankxe2x80x9d) has a limitation on its capacity. To deal with this problem, a construction has been proposed in which a large-capacity ink tank (or xe2x80x9cmain tankxe2x80x9d) is provided separately from this subtank to supply ink from the main tank to the subtank while the printing is not performed.
As the method for supplying ink from the main tank to the subtank a pit-in method is available. In this method the main tank is located at a desired position in the ink jet printing apparatus other than the carriage and supplies ink to the subtank through a predetermined ink supply port when the subtank comes to a predetermined position. The subtank is often formed with an atmosphere communication port to keep an inner pressure equal to the atmospheric pressure and with a suction port to make the inner pressure negative when the ink is supplied. These ports or openings are provided with a porous liquid-repellent film of fluororesin that only passes gases, not liquids, so that the ink in the tank does not leak out. An example that uses the porous liquid-repellent film of fluororesin for the atmosphere communication port is an invention disclosed in Japanese Patent Application Laid-open No. 5-201021 (1993). In this invention, a porous liquid-repellent film that is applied a liquid-repellency application agent in advance to enhance its repellency is attached to the atmosphere communication port and, heat is applied from inside the tank to the porous liquid-repellent film to fuse it to the tank body.
Thermally fusing the porous liquid-repellent film to the subtank may cause the following problem. A portion of the subtank to which the film is to be fused is heated to a temperature close to a melting point of polypropylene, which is the material of the subtank. The heat applied, however, gets applied not only to the portion where the film is to be fused but also to other portions, changing the surface of the porous film, which in turn degrades the liquid repellency of the porous film.
The deteriorated liquid repellency of the porous film results in water in the container easily permeating to the outside through the atmosphere communication port. If the liquid is ink, the degradation of the liquid repellency of the porous film increases the viscosity of the ink, changing its physical property.
Considering the above-mentioned problems experienced with the conventional apparatus, it is an object of the present invention to provide a method of manufacturing a structural body, which has an opening attached with a porous film kept in a good liquid-repellent condition, a liquid tank and an ink jet printing apparatus and also to provide an ink jet printing apparatus.
It is also an object of the present invention to provide a method of manufacturing with ease and at low cost a structural body which has a communication portion for communicating an interior of the structural body, into which a liquid is introduced, to an exterior through a gas-liquid separation member that passes only gasses, and which can keep the liquid-repellent performance of the gas-liquid separation member in good condition.
One aspect of the present invention provides a method of manufacturing a structural body, wherein the structural body has a communication portion for communicating an interior of the structural body to an exterior thereof and a gas-liquid separation member permeable only to gases and arranged on the communication portion, the method comprising the steps of: mounting the gas-liquid separation member to the communication portion; and after the mounting step, applying repellency to the gas-liquid separation member with a repellency application agent.
Another aspect of the present invention provides a method of manufacturing a liquid tank, wherein the liquid tank has a negative pressure introducing portion for introducing a negative pressure into the liquid tank, a liquid intake portion for drawing a liquid into the liquid tank by the negative pressure introduced by the negative pressure introducing portion, and a gas-liquid separation member permeable only to gases and arranged on the negative pressure introducing portion, the method comprising the steps of: mounting the gas-liquid separation member to the negative pressure introducing portion; and after the mounting step, applying repellency to the gas-liquid separation member with a repellency application agent.
Still another aspect of the present invention provides a method of manufacturing a liquid tank, wherein the liquid tank has a container body for accommodating a liquid, an opening for drawing out the liquid, an atmosphere communication port for communicating the container body to the atmosphere, and a gas-liquid separation member permeable only to gases and arranged on the atmosphere communication port, the method comprising the steps of: mounting the gas-liquid separation member to the atmosphere communication port; and after the mounting step, applying repellency to the gas-liquid separation member with a repellency application agent.
A further aspect of the present invention provides a method of manufacturing an ink jet printing apparatus, wherein the ink jet printing apparatus has a liquid tank, the liquid tank having a negative pressure introducing portion for introducing a negative pressure into the liquid tank and a liquid intake portion for drawing a liquid into the liquid tank by the negative pressure introduced by the negative pressure introducing portion; a negative pressure generation mechanism for applying a negative pressure to the liquid tank to introduce the liquid into the liquid tank; and a gas-liquid separation member permeable only to gases and arranged in a vicinity of a joint portion of the negative pressure generation mechanism with the negative pressure introducing portion; the method comprising the steps of: mounting the gas-liquid separation member to the negative pressure introducing portion; and after the mounting step, applying repellency to the gas-liquid separation member with a repellency application agent.
A further aspect of the present invention provides an ink jet printing apparatus which has a negative pressure generation mechanism for applying a negative pressure to the liquid tank manufactured by the method described above to introduce a liquid.
With the construction described above, since the gas-liquid separation member is subjected to the repellency application processing after it has been mounted to the communication portion, no additional heat is applied to the gas-liquid separation member after the repellency application processing. Therefore, the gas-liquid separation member does not change in property, thus maintaining high repellency.
Since the liquid tank manufactured by the liquid tank manufacturing method described above can maintain high repellency at all times, the gas-liquid separation can be performed reliably.
Therefore, in the ink jet printing apparatus incorporating such a liquid tank, ink can be supplied from the main tank to the liquid tank with no ink leakage.
A further aspect of the present invention provides a method of manufacturing a structural body, wherein the structural body has a communication portion for communicating an interior of the structural body, into which a liquid is introduced, to an exterior thereof through a gas-liquid separation member permeable only to gases, the method comprising the steps of: coating the gas-liquid separation member with a repellency application agent; and after the coating step, heating the gas-liquid separation member and integrally joining at least an outer peripheral portion of the gas-liquid separation member to the communication portion.
Further, the liquid tank of the invention may include a negative pressure introducing portion for introducing a negative pressure into the liquid tank, a liquid intake portion for drawing a liquid into the liquid tank by the negative pressure introduced by the negative pressure introducing portion, a gas-liquid separation member permeable only to gases and arranged on the negative pressure introducing portion, and a repellency application agent coated on the gas-liquid separation member, wherein the gas-liquid separation member is heated to evaporate solvent contained in the repellency application agent and this heating is utilized to integrally join an outer periphery of the gas-liquid separation member to the negative pressure introducing portion.
Furthermore, the liquid tank of the invention may include a casing for accommodating a liquid, an opening for drawing out the liquid from the casing, an atmosphere communication portion for communicating an interior of the casing to the atmosphere, a gas-liquid separation member permeable only to gases and arranged on the atmosphere communication portion, and a repellency application agent coated on the gas-liquid separation member, wherein the gas-liquid separation member is heated to evaporate solvent contained in the repellency application agent and this heating is utilized to integrally join an outer periphery of the gas-liquid separation member to the negative pressure introducing portion.
A further aspect of the invention provides a head cartridge comprising the liquid tank of the above construction and a liquid ejection head to which a liquid is supplied from the liquid tank and which has nozzles for ejecting the liquid.
A further aspect of the invention provides an ink jet printing apparatus comprising a mounting portion and a negative pressure generation means, the mounting portion having the liquid tank of the above construction and a liquid ejection head to which a liquid is supplied from the liquid tank and which has nozzles for ejecting the liquid, the negative pressure generation means being adapted to apply a negative pressure to the liquid tank to introduce the liquid into the tank.
A further aspect of the invention provides an ink jet printing apparatus comprising a mounting portion capable of mounting the head cartridge of this invention, and a negative pressure generation means for applying a negative pressure to the liquid tank of the head cartridge to introduce a liquid into the tank.
The above and other objects, effects, features and advantages of the present invention will become more apparent from the following description of embodiments thereof taken in conjunction with the accompanying drawings.